From 0044ae11e8be86b5e39857d47017417d4cda00f2 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 13 Apr 2021 14:23:14 +0800 Subject: [PATCH] btrfs: make free space cache size consistent across different PAGE_SIZE Currently free space cache inode size is determined by two factors: - block group size - PAGE_SIZE This means, for the same sized block groups, with different PAGE_SIZE, it will result in different inode sizes. This will not be a good thing for subpage support, so change the requirement for PAGE_SIZE to sectorsize. Now for the same 4K sectorsize btrfs, it should result the same inode size no matter what the PAGE_SIZE is. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- fs/btrfs/block-group.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 6d5c4e4..c42b652 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -2505,7 +2505,7 @@ static int cache_save_setup(struct btrfs_block_group *block_group, struct extent_changeset *data_reserved = NULL; u64 alloc_hint = 0; int dcs = BTRFS_DC_ERROR; - u64 num_pages = 0; + u64 cache_size = 0; int retries = 0; int ret = 0; @@ -2617,20 +2617,20 @@ again: * taking up quite a bit since it's not folded into the other space * cache. */ - num_pages = div_u64(block_group->length, SZ_256M); - if (!num_pages) - num_pages = 1; + cache_size = div_u64(block_group->length, SZ_256M); + if (!cache_size) + cache_size = 1; - num_pages *= 16; - num_pages *= PAGE_SIZE; + cache_size *= 16; + cache_size *= fs_info->sectorsize; ret = btrfs_check_data_free_space(BTRFS_I(inode), &data_reserved, 0, - num_pages); + cache_size); if (ret) goto out_put; - ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages, - num_pages, num_pages, + ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, cache_size, + cache_size, cache_size, &alloc_hint); /* * Our cache requires contiguous chunks so that we don't modify a bunch -- 2.7.4